public class NumberOfNines {
    public static void main(String[] args) {
        int i = 1;
        int count = 0;
        for(i = 1;i < 100;i++) {
            if(i%10==9) {
                count++;
            }
            if(i/10 == 9) {
                count++;
            }
        }
        System.out.println(count);
    }
}
